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71.
China's 12th Five-Year Plan (2011–2015) envisages that shale gas and coal will be central to its energy future. However, for China to meet the energy security and climate change objectives set out in its 12th Five-Year Plan it will be reliant on the widespread commercial deployment of two key technologies; hydraulic fracturing combined with horizontal drilling for shale gas, and carbon capture and storage (CCS) for coal. China is moving to acquire these technologies through technology transfer and diffusion from the US, but progress has been slow, and neither is currently available in China on a commercial scale. Drawing on interviews in the US and China, this article argues that China's expectation of technology from the US may well be disappointed because of factors unique to the US institutional environment that have made the development of fracking technology possible and hinder the development of CCS technology at a commercial scale.Policy relevanceIf China is to meet the energy security and climate change objectives set out in its 12th Five-Year Plan it will be reliant on the widespread commercial deployment of fracking and clean coal technologies. While China expects to acquire these technologies via technology transfer and diffusion from the US, progress has been slow. Because of factors unique to the US institutional environment the availability of both technologies on a commercial scale in China is unlikely in the coming years. As a result, Chinese policy makers would be well-advised not to count on these technologies to meet their energy and climate goals. 相似文献
72.
The Characteristics of Atmospheric Ice Nuclei Measured at Different Altitudes in the Huangshan Mountains in Southeast China简 总被引:3,自引:0,他引:3
The concentration of ice nuclei (IN) and the relationship with aerosol particles were measured and analyzed using three 5-L mixing cloud chambers and a static diffusion cloud chamber at three altitudes in the Huangshan Mountains in Southeast China from May to September 2011.The results showed that the mean total number concentration of IN on the highest peak of the Huangshan Mountains at an activation temperature (Ta) of-20℃C was 16.6 L-1.When the supersaturation with respect to water (Sw) and with respect to ice (Si) were set to 5%,the average number concentrations of IN measured at an activation temperature of-20℃C by the static diffusion cloud chamber were 0.89 and 0.105 L-1,respectively.A comparison of the concentrations of IN at three different altitudes showed that the concentration of IN at the foot of the mountains was higher than at the peak.A further calculation of the correlation between IN and the concentrations of aerosol particles of different size ranges showed that the IN concentration was well correlated with the concentration of aerosol particles in the size range of 1.2-20 μtm.It was also found that the IN concentration varied with meteorological conditions,such as wind speed,with higher IN concentrations often observed on days with strong wind.An analysis of the backward trajectories of air masses showed that low IN concentrations were often related to air masses travelling along southwest pathways,while higher IN concentrations were usually related to those transported along northeast pathways. 相似文献
73.
This article attempts to disentangle the determinants of the adoption of renewable energy support policies in developing and emerging countries. By analyzing policies already implemented in industrialized countries, we focus on the diffusion but not the invention of climate-relevant policies. We look at four different types of policies (renewable energy targets, feed-in tariffs, other financial incentives and framework policies) and consider both domestic factors and international diffusion mechanisms utilizing a discrete-time events history model with a logit link on a self-compiled dataset of grid-based electricity policy adoption in 112 developing and emerging countries from 1998 to 2009. In general, we find stronger support for the domestic determinants of policy adoption, but also substantial influence of international factors. Countries with a larger population and more wealth have a higher probability of adopting renewable energy policies. Only in some specific cases do natural endowments for producing renewable energy encourage governments to adopt policies, and hydro power resources even correlate negatively with the adoption of targets. Among the international determinants, emulation from colonial peers and membership within the EU seem to facilitate policy adoption. International climate finance is less relevant, as the Global Environmental Facility and the Clean Development Mechanism may only increase the adoption of frameworks and targets, but they have no influence on tariffs and incentives. 相似文献
74.
States have been widely criticized for failing to advance the international climate regime. Many observers now believe that a “new” climate governance is emerging through transnational and/or local forms of action that will eventually plug the resulting governance gaps. Yet states, which remain oddly absent from most discussions of the “new” governance, will remain key players as governance becomes more polycentric. This paper introduces a special issue that explores the ability of states to rise to these interconnected challenges through the analytical prism of policy innovation. It reveals that policy innovation is much more multi-dimensional than is often thought; it encompasses three vital activities: invention (centering on the ‘source’ of new policy elements), diffusion (that produces different ‘patterns’ of policy adoption), and the evaluation of the ‘effects’ that such innovations create in reality. The papers, which range from qualitative case studies to large ‘n’ quantitative studies, offer new insights into the varied roles that states play in relation to all three.They show, for instance that: the policy activity of states has risen dramatically in the past decade; that state innovation is affected to similar degrees by internal and external factors; and that policies that offer flexibility to target groups on how to meet policy goals are most effective but that voluntary reporting requirements are ineffective. This paper draws upon these and many other insights to offer a much more nuanced reflection on the future of climate governance; one that deservedly puts states at the front and center of analysis. 相似文献
75.
为了探讨绥中一次暴雪伴雷电天气过程的成因,利用常规观测资料、NCEP每6h间隔的1°×1°的再分析资料和营口多普勒雷达的资料,分析此过程的天气形势特点、高低空急流的作用、雷达回波的特征及反映动力、热力和水汽条件的相关物理量场的特征。结果发现:雷电发生在对流层中层的西南风急流和底层偏东风均处在最强的时刻,当对流云团发展到-20℃温度层时,温差起电产生雷电;雷电发生在低层850hPa附近存在的逆温层消失之后,同时配合低层水汽的辐合,产生了暴雪天气;雷电和强降雪发生在大气底层南风和北风转换的过程中,强降雪的时间与冷空气扩散加强的时间比较一致,当冷空气扩散到整个大气底层时强降雪结束;引起雷电和强降雪的对流不稳定层结主要处在对流层中层,并为上升运动的发生提供了动力和热力条件,促使雷电发生和强降雪的维持。 相似文献
76.
斜压罗斯贝变形半径优化的误差相关尺度及其对最优插值效果的改进 总被引:2,自引:0,他引:2
利用最优插值方法进行三维温盐场重构时,如何正确估算背景场误差协方差至关重要。针对背景场误差协方差主要取决于误差相关尺度的问题,本文提出了用中国东部海域及其附近海域的最新的高分辨率气候态数据进行斜压罗斯贝变形半径优化其误差相关尺度计算的研究方案和技术途径;对比分析了均一化相关尺度方案和法国ISAS系统尺度方案,讨论了变形半径对最优插值的影响。结果表明:均一化相关尺度方案的均方根误差小于ISAS方案,但温度场过于平滑,难以刻画一些重要的物理现象;相比而言,本文提出的基于变形半径的相关尺度方案在取2倍变形半径时,不仅均方根误差在各水平层较小,且温度场能够更好地刻画四国海盆海域涡旋及黑潮影响的温度场三维结构。由于实际海洋中各层物理过程的尺度存在差异,实际应用时各层的最优尺度设置也应有所不同。 相似文献
77.
HUANG Rui Xin 《海洋学报(英文版)》2014,33(3):19-39
Study of oceanic circulation and climate requires models which can simulate tracer eddy diffusion and ad vection accurately. It is shown that the traditional Eulerian coordinates can introduce large artificial hori zontal diffusivity/viscosity due to the incorrect alignment of the axis. Therefore, such models can smear sharp fronts and introduce other numerical artifacts. For simulation with relatively low resolution, large lateral diffusion was explicitly used in models; therefore, such numerical diffusion may not be a problem. However, with the increase of horizontal resolution, the artificial diffusivity/viscosity associated with hori zontal advection in the commonly used Eulerian coordinates may become one of the most challenging ob stacles for modeling the ocean circulation accurately. Isopycnal eddy diffusion (mixing) has been widely used in numerical models. The common wisdom is that mixing along isopycnal is energy free. However, a careful examination reveals that this is not the case. In fact, eddy diffusion can be conceptually separated into two steps: stirring and subscale diffusion. Due to the thermobaric effect, stirring, or exchanging water masses, along isopycnal surface is associated with the change of GPE in the mean state. This is a new type of instability, called the thermobaric instability. In addition, due to cabbeling subscale diffusion of water parcels always leads to the release of GPE. The release of GPE due to isopycnal stirring and subscale diffusion may lead to the thermobaric instability. 相似文献
78.
This study investigates the physical conditions (water depth, current speed, salinity, temperature) in Lianzhou Bay, a shallow coastal bay in southern China, during two expeditions in the dry and wet seasons of 2011. Based on these expedition data, basic hydrodynamic parameters like Brunt-Väisälä Frequency, Richardson Number, Rossby radius, and Resonance Period are calculated. The results show that Lianzhou Bay is characterized by comparatively small quantity of freshwater input and weak stratification. Strong tides, which are spatially uniform within the bay, cause turbulent mixing. Residence time of the water is shorter in winter due to a stronger coastal current in that season. Consideration of the water movement may help to reduce the harmful ecological impact of aquaculture waste water discharge. 相似文献
79.
80.
Cooling rates based on the retrograde diffusion of Fe2+ and Mg between garnet and biotite inclusions commonly show two contrasting scenarios: a) narrow closure temperature range with apparent absence of retrograde diffusion; or b) high result dispersion due to compositional variations in garnet and biotite. Cooling rates from migmatites, felsic and mafic granulites from Ribeira Fold Belt (SE Brazil) also show these two scenarios. Although the former can be explained by very fast cooling, the latter is often the result of open-system behaviour caused by deformation. Retrogressive cooling during the exhumation of granulite-facies rocks is often processed by thrusting and shearing which may cause plastic deformation, fractures and cracks in the garnet megablasts, allowing chemical diffusion outside the garnet megablast – biotite inclusion system.However, a careful use of garnets and biotites with large Fe/Mg variation and software that reduces result dispersion provides a good correlation between closure temperatures and the size of biotite inclusions which are mostly due to diffusion and compositional readjustment to thermal evolution during retrogression.Results show that felsic and mafic granulites have low cooling rates (1–2 °C/Ma) at higher temperatures and high cooling rates (∼100 °C/Ma) at lower temperatures, suggesting a two-step cooling/exhumation process, whereas migmatites show a small decrease in cooling rates during cooling (from 2.0 to 0.5 °C/Ma). These results agree with previously obtained thermochronological data, which indicates that this method is a valid tool to obtain meaningful petrological cooling rates in complex high-grade orogenic belts, such as the Ribeira Fold Belt. 相似文献